Stereoselective amino alcohol synthesis via chemoselective electrocatalytic radical cross-couplings

Nature Chemistry, Год журнала: 2025, Номер unknown

Опубликована: Янв. 3, 2025

Язык: Английский

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Cobalt-Catalyzed Intermolecular Hydrofunctionalization of Alkenes: Evidence for a Bimetallic Pathway

Journal of the American Chemical Society, Год журнала: 2019, Номер 141(18), С. 7250 - 7255

Опубликована: Апрель 23, 2019

A functional group tolerant cobalt-catalyzed method for the intermolecular hydrofunctionalization of alkenes with oxygen- and nitrogen-based nucleophiles is reported. This protocol features a strategic use hypervalent iodine(III) reagents that enables mechanistic shift from conventional cobalt–hydride catalysis. Key evidence was found supporting unique bimetallic-mediated rate-limiting step involving two distinct cobalt(III) species, which new carbon–heteroatom bond formed.

Язык: Английский

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Iron and cobalt catalysis: new perspectives in synthetic radical chemistry

Chemical Society Reviews, Год журнала: 2020, Номер 49(23), С. 8501 - 8542

Опубликована: Янв. 1, 2020

Iron and cobalt complexes are at the origin of high valuable synthetic pathways involving radical intemediates.

Язык: Английский

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1,3‐Difunctionalizations of [1.1.1]Propellane via 1,2‐Metallate Rearrangements of Boronate Complexes

Angewandte Chemie International Edition, Год журнала: 2020, Номер 59(10), С. 3917 - 3921

Опубликована: Янв. 8, 2020

1,3-Disubstituted bicyclo[1.1.1]pentanes (BCPs) are valuable bioisosteres of para-substituted aromatic rings. The most direct route to these structures is via multicomponent ring-opening reactions [1.1.1]propellane. However, challenges associated with transformations mean that difunctionalized BCPs more commonly prepared by multistep reaction sequences BCP-halide intermediates. Herein, we report three- and four-component 1,3-difunctionalizations [1.1.1]propellane organometallic reagents, organoboronic esters, a variety electrophiles. This process achieved trapping intermediate BCP-metal species boronic esters form boronate complexes, which versatile intermediates whose electrophile-induced 1,2-metallate rearrangement chemistry enables broad range C-C bond-forming reactions.

Язык: Английский

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Catalytic Asymmetric Radical–Polar Crossover Hydroalkoxylation

Journal of the American Chemical Society, Год журнала: 2019, Номер 141(44), С. 17527 - 17532

Опубликована: Окт. 23, 2019

Asymmetric intramolecular hydrofunctionalization of tertiary allylic alcohols is described. This metal hydride-mediated catalytic radical–polar crossover reaction delivers corresponding epoxides in good to high enantioselectivity and constitutes the first example asymmetric hydrogen atom transfer-initiated process. A series modified cobalt salen complexes has proven optimal for achieving efficiency induction. Experimental data suggest that cationic may be involved enantiodetermining step, where cation−π interactions catalyst contribute

Язык: Английский

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Radical‐Based Synthesis and Modification of Amino Acids

Angewandte Chemie International Edition, Год журнала: 2020, Номер 60(3), С. 1098 - 1115

Опубликована: Авг. 26, 2020

Abstract Amino acids (AAs) are key structural motifs with widespread applications in organic synthesis, biochemistry, and material sciences. Recently, the development of milder more versatile radical‐based procedures, use strategies relying on radical chemistry for synthesis modification AAs has gained increased attention, as they allow rapid access to libraries novel unnatural containing a wide range motifs. In this Minireview, we provide broad overview advancements made field during last decade, focusing methods de novo α‐, β‐, γ‐AAs, well selective derivatisation canonical non‐canonical α‐AAs.

Язык: Английский

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1,2-Amino Alcohols via Cr/Photoredox Dual-Catalyzed Addition of α-Amino Carbanion Equivalents to Carbonyls

Journal of the American Chemical Society, Год журнала: 2020, Номер 142(5), С. 2168 - 2174

Опубликована: Янв. 10, 2020

Herein, we report the synthesis of protected 1,2-amino alcohols starting from carbonyl compounds and α-silyl amines. The reaction is enabled by a Cr/photoredox dual catalytic system that allows in situ generation α-amino carbanion equivalents which act as nucleophiles. unique nature this was demonstrated through aminoalkylation ketones an acyl silane, classes electrophiles were previously unreactive toward addition alkyl-Cr reagents. Overall, broadens scope Cr-mediated alkylations discloses underexplored retrosynthetic strategy for alcohols.

Язык: Английский

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Catalyst- and Silane-Controlled Enantioselective Hydrofunctionalization of Alkenes by Cobalt-Catalyzed Hydrogen Atom Transfer and Radical-Polar Crossover

Journal of the American Chemical Society, Год журнала: 2020, Номер 142(31), С. 13481 - 13490

Опубликована: Июль 10, 2020

The catalytic enantioselective synthesis of tetrahydrofurans, which are found in the structures many biologically active natural products, via a transition-metal-catalyzed hydrogen atom transfer (TM-HAT) and radical-polar crossover (RPC) mechanism is described herein. Hydroalkoxylation nonconjugated alkenes proceeded efficiently with excellent enantioselectivity (up to 94% ee) using suitable chiral cobalt catalyst, N-fluoro-2,4,6-collidinium tetrafluoroborate, diethylsilane. Surprisingly, absolute configuration product was highly dependent on steric hindrance silane. Slow addition silane, dioxygen effect solvent, thermal dependence, DFT calculation results supported unprecedented scenario two competing selective mechanisms. For less-hindered diethylsilane, high concentration diffused carbon-centered radicals invoked diastereoenrichment an alkylcobalt(III) intermediate by radical chain reaction, eventually determined product. On other hand, more hindered silane resulted less opportunity for instead facilitating kinetic resolution during late-stage nucleophilic displacement alkylcobalt(IV) intermediate.

Язык: Английский

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Selected Topics in the Syntheses of Bicyclo[1.1.1]Pentane (BCP) Analogues

Asian Journal of Organic Chemistry, Год журнала: 2019, Номер 9(1), С. 8 - 22

Опубликована: Окт. 24, 2019

Abstract This Minireview focuses on selected topics in the syntheses of bicyclo[1.1.1]pentane (BCP) analogues. A brief historical introduction was included. The content covers various synthetic routes 1‐substituted and 1,3‐disubstituted BCPs. Selective examples synthetically useful building blocks are summarized for each category organic chemists’ medicinal reference. compare‐and‐contrast analysis is also applied to evaluate these demonstrate progress strategic functional group transformations using modern methodologies. By systematically analyzing strategies access strained molecules, we hope that this will provide inspirations future developments area.

Язык: Английский

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Der “Persistent Radical Effect” in der organischen Chemie

Angewandte Chemie, Год журнала: 2019, Номер 132(1), С. 74 - 110

Опубликована: Май 22, 2019

Abstract Radikal‐Radikal‐Kupplungen sind nahezu diffusionskontrollierte Prozesse. Daher selektive Kreuzkupplungen zweier unterschiedlicher Radikale schwierig zu realisieren und stellen somit synthetisch nicht wertvolle Prozesse dar. Wenn die beiden allerdings eine unterschiedliche Lebensdauer aufweisen in gleichen Raten gebildet werden, wird Kreuzkupplung zum dominierenden Prozess. Die hohe Kreuzselektivität basiert auf einem kinetischen Phänomen, dem “Persistent Radical Effect” (PRE). In diesem Aufsatz von Simulationen einfacher Modellsysteme gestützte Erklärung des PRE geliefert. Weiter werden Stabilität Radikalen Bezug ihre verschiedene Beispiele für PRE‐vermittelte der Synthese diskutiert. Es gezeigt, dass Kupplungen persistenter mit transienten beschränkt ist. Der einhergehender hoher greift bereits, wenn ein Kupplungspartner langlebiger als das andere transiente Radikal Diese Tatsache erweitert signifikant Anwendungsgebiet PRE‐vermittelter Radikalchemie. Dieser ist zwei Teile aufgeteilt: 1) Kupplung oder organischer 2) Radikal‐Metall‐Kreuzungsreaktionen; hierbei Metall‐zentrierte Radikalspezies allgemeiner langlebige Übergangsmetallkomplexe, welche reagieren, diskutiert – Gebiet, jüngst stark expandiert

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